st: details of how the impute command work

I have a rather simple question. I am trying to figure out exactly
what the -impute- command in Stata does to estimate missing values.
The help files in Stata are not very helpful. From what I have found
on the internet, it appears -impute- is a regression-based method to
estimate missing values based on other variables in the data set.
However, the help files also say that -impute- "organizes the cases by
patterns of missing data so that the missing-value regressions can be
conducted efficiently." Does anyone know what this entails? I need to
include some mention of this in my methods section.

Thanks for your help,
Tim Hale

-----------------------------------------------------
Tim Hale
Graduate Assistant
University of Alabama at Birmingham
Department of Sociology